Merge tag 'afs-next-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS updates from David Howells:
 "kAFS filesystem driver overhaul.

  The major points of the overhaul are:

   (1) Preliminary groundwork is laid for supporting network-namespacing
       of kAFS. The remainder of the namespacing work requires some way
       to pass namespace information to submounts triggered by an
       automount. This requires something like the mount overhaul that's
       in progress.

   (2) sockaddr_rxrpc is used in preference to in_addr for holding
       addresses internally and add support for talking to the YFS VL
       server. With this, kAFS can do everything over IPv6 as well as
       IPv4 if it's talking to servers that support it.

   (3) Callback handling is overhauled to be generally passive rather
       than active. 'Callbacks' are promises by the server to tell us
       about data and metadata changes. Callbacks are now checked when
       we next touch an inode rather than actively going and looking for
       it where possible.

   (4) File access permit caching is overhauled to store the caching
       information per-inode rather than per-directory, shared over
       subordinate files. Whilst older AFS servers only allow ACLs on
       directories (shared to the files in that directory), newer AFS
       servers break that restriction.

       To improve memory usage and to make it easier to do mass-key
       removal, permit combinations are cached and shared.

   (5) Cell database management is overhauled to allow lighter locks to
       be used and to make cell records autonomous state machines that
       look after getting their own DNS records and cleaning themselves
       up, in particular preventing races in acquiring and relinquishing
       the fscache token for the cell.

   (6) Volume caching is overhauled. The afs_vlocation record is got rid
       of to simplify things and the superblock is now keyed on the cell
       and the numeric volume ID only. The volume record is tied to a
       superblock and normal superblock management is used to mediate
       the lifetime of the volume fscache token.

   (7) File server record caching is overhauled to make server records
       independent of cells and volumes. A server can be in multiple
       cells (in such a case, the administrator must make sure that the
       VL services for all cells correctly reflect the volumes shared
       between those cells).

       Server records are now indexed using the UUID of the server
       rather than the address since a server can have multiple
       addresses.

   (8) File server rotation is overhauled to handle VMOVED, VBUSY (and
       similar), VOFFLINE and VNOVOL indications and to handle rotation
       both of servers and addresses of those servers. The rotation will
       also wait and retry if the server says it is busy.

   (9) Data writeback is overhauled. Each inode no longer stores a list
       of modified sections tagged with the key that authorised it in
       favour of noting the modified region of a page in page->private
       and storing a list of keys that made modifications in the inode.

       This simplifies things and allows other keys to be used to
       actually write to the server if a key that made a modification
       becomes useless.

  (10) Writable mmap() is implemented. This allows a kernel to be build
       entirely on AFS.

  Note that Pre AFS-3.4 servers are no longer supported, though this can
  be added back if necessary (AFS-3.4 was released in 1998)"

* tag 'afs-next-20171113' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs: (35 commits)
  afs: Protect call->state changes against signals
  afs: Trace page dirty/clean
  afs: Implement shared-writeable mmap
  afs: Get rid of the afs_writeback record
  afs: Introduce a file-private data record
  afs: Use a dynamic port if 7001 is in use
  afs: Fix directory read/modify race
  afs: Trace the sending of pages
  afs: Trace the initiation and completion of client calls
  afs: Fix documentation on # vs % prefix in mount source specification
  afs: Fix total-length calculation for multiple-page send
  afs: Only progress call state at end of Tx phase from rxrpc callback
  afs: Make use of the YFS service upgrade to fully support IPv6
  afs: Overhaul volume and server record caching and fileserver rotation
  afs: Move server rotation code into its own file
  afs: Add an address list concept
  afs: Overhaul cell database management
  afs: Overhaul permit caching
  afs: Overhaul the callback handling
  afs: Rename struct afs_call server member to cm_server
  ...

1 files changed, 109 insertions, 50 deletions

diff --git a/fs/afs/flock.c b/fs/afs/flock.c
index 3191dff2c156..7571a5dfd5a3 100644
--- a/fs/afs/flock.c
+++ b/fs/afs/flock.c
@@ -14,48 +14,17 @@
 #define AFS_LOCK_GRANTED	0
 #define AFS_LOCK_PENDING	1
 
+struct workqueue_struct *afs_lock_manager;
+
 static void afs_fl_copy_lock(struct file_lock *new, struct file_lock *fl);
 static void afs_fl_release_private(struct file_lock *fl);
 
-static struct workqueue_struct *afs_lock_manager;
-static DEFINE_MUTEX(afs_lock_manager_mutex);
-
 static const struct file_lock_operations afs_lock_ops = {
 	.fl_copy_lock		= afs_fl_copy_lock,
 	.fl_release_private	= afs_fl_release_private,
 };
 
 /*
- * initialise the lock manager thread if it isn't already running
- */
-static int afs_init_lock_manager(void)
-{
-	int ret;
-
-	ret = 0;
-	if (!afs_lock_manager) {
-		mutex_lock(&afs_lock_manager_mutex);
-		if (!afs_lock_manager) {
-			afs_lock_manager = alloc_workqueue("kafs_lockd",
-							   WQ_MEM_RECLAIM, 0);
-			if (!afs_lock_manager)
-				ret = -ENOMEM;
-		}
-		mutex_unlock(&afs_lock_manager_mutex);
-	}
-	return ret;
-}
-
-/*
- * destroy the lock manager thread if it's running
- */
-void __exit afs_kill_lock_manager(void)
-{
-	if (afs_lock_manager)
-		destroy_workqueue(afs_lock_manager);
-}
-
-/*
  * if the callback is broken on this vnode, then the lock may now be available
  */
 void afs_lock_may_be_available(struct afs_vnode *vnode)
@@ -99,6 +68,100 @@ static void afs_grant_locks(struct afs_vnode *vnode, struct file_lock *fl)
 }
 
 /*
+ * Get a lock on a file
+ */
+static int afs_set_lock(struct afs_vnode *vnode, struct key *key,
+			afs_lock_type_t type)
+{
+	struct afs_fs_cursor fc;
+	int ret;
+
+	_enter("%s{%x:%u.%u},%x,%u",
+	       vnode->volume->name,
+	       vnode->fid.vid,
+	       vnode->fid.vnode,
+	       vnode->fid.unique,
+	       key_serial(key), type);
+
+	ret = -ERESTARTSYS;
+	if (afs_begin_vnode_operation(&fc, vnode, key)) {
+		while (afs_select_fileserver(&fc)) {
+			fc.cb_break = vnode->cb_break + vnode->cb_s_break;
+			afs_fs_set_lock(&fc, type);
+		}
+
+		afs_check_for_remote_deletion(&fc, fc.vnode);
+		afs_vnode_commit_status(&fc, vnode, fc.cb_break);
+		ret = afs_end_vnode_operation(&fc);
+	}
+
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Extend a lock on a file
+ */
+static int afs_extend_lock(struct afs_vnode *vnode, struct key *key)
+{
+	struct afs_fs_cursor fc;
+	int ret;
+
+	_enter("%s{%x:%u.%u},%x",
+	       vnode->volume->name,
+	       vnode->fid.vid,
+	       vnode->fid.vnode,
+	       vnode->fid.unique,
+	       key_serial(key));
+
+	ret = -ERESTARTSYS;
+	if (afs_begin_vnode_operation(&fc, vnode, key)) {
+		while (afs_select_current_fileserver(&fc)) {
+			fc.cb_break = vnode->cb_break + vnode->cb_s_break;
+			afs_fs_extend_lock(&fc);
+		}
+
+		afs_check_for_remote_deletion(&fc, fc.vnode);
+		afs_vnode_commit_status(&fc, vnode, fc.cb_break);
+		ret = afs_end_vnode_operation(&fc);
+	}
+
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
+ * Release a lock on a file
+ */
+static int afs_release_lock(struct afs_vnode *vnode, struct key *key)
+{
+	struct afs_fs_cursor fc;
+	int ret;
+
+	_enter("%s{%x:%u.%u},%x",
+	       vnode->volume->name,
+	       vnode->fid.vid,
+	       vnode->fid.vnode,
+	       vnode->fid.unique,
+	       key_serial(key));
+
+	ret = -ERESTARTSYS;
+	if (afs_begin_vnode_operation(&fc, vnode, key)) {
+		while (afs_select_current_fileserver(&fc)) {
+			fc.cb_break = vnode->cb_break + vnode->cb_s_break;
+			afs_fs_release_lock(&fc);
+		}
+
+		afs_check_for_remote_deletion(&fc, fc.vnode);
+		afs_vnode_commit_status(&fc, vnode, fc.cb_break);
+		ret = afs_end_vnode_operation(&fc);
+	}
+
+	_leave(" = %d", ret);
+	return ret;
+}
+
+/*
  * do work for a lock, including:
  * - probing for a lock we're waiting on but didn't get immediately
  * - extending a lock that's close to timing out
@@ -122,7 +185,7 @@ void afs_lock_work(struct work_struct *work)
 
 		/* attempt to release the server lock; if it fails, we just
 		 * wait 5 minutes and it'll time out anyway */
-		ret = afs_vnode_release_lock(vnode, vnode->unlock_key);
+		ret = afs_release_lock(vnode, vnode->unlock_key);
 		if (ret < 0)
 			printk(KERN_WARNING "AFS:"
 			       " Failed to release lock on {%x:%x} error %d\n",
@@ -143,10 +206,10 @@ void afs_lock_work(struct work_struct *work)
 			BUG();
 		fl = list_entry(vnode->granted_locks.next,
 				struct file_lock, fl_u.afs.link);
-		key = key_get(fl->fl_file->private_data);
+		key = key_get(afs_file_key(fl->fl_file));
 		spin_unlock(&vnode->lock);
 
-		ret = afs_vnode_extend_lock(vnode, key);
+		ret = afs_extend_lock(vnode, key);
 		clear_bit(AFS_VNODE_LOCKING, &vnode->flags);
 		key_put(key);
 		switch (ret) {
@@ -177,12 +240,12 @@ void afs_lock_work(struct work_struct *work)
 			BUG();
 		fl = list_entry(vnode->pending_locks.next,
 				struct file_lock, fl_u.afs.link);
-		key = key_get(fl->fl_file->private_data);
+		key = key_get(afs_file_key(fl->fl_file));
 		type = (fl->fl_type == F_RDLCK) ?
 			AFS_LOCK_READ : AFS_LOCK_WRITE;
 		spin_unlock(&vnode->lock);
 
-		ret = afs_vnode_set_lock(vnode, key, type);
+		ret = afs_set_lock(vnode, key, type);
 		clear_bit(AFS_VNODE_LOCKING, &vnode->flags);
 		switch (ret) {
 		case -EWOULDBLOCK:
@@ -213,7 +276,7 @@ void afs_lock_work(struct work_struct *work)
 				clear_bit(AFS_VNODE_READLOCKED, &vnode->flags);
 				clear_bit(AFS_VNODE_WRITELOCKED, &vnode->flags);
 				spin_unlock(&vnode->lock);
-				afs_vnode_release_lock(vnode, key);
+				afs_release_lock(vnode, key);
 				if (!list_empty(&vnode->pending_locks))
 					afs_lock_may_be_available(vnode);
 			}
@@ -255,7 +318,7 @@ static int afs_do_setlk(struct file *file, struct file_lock *fl)
 	struct inode *inode = file_inode(file);
 	struct afs_vnode *vnode = AFS_FS_I(inode);
 	afs_lock_type_t type;
-	struct key *key = file->private_data;
+	struct key *key = afs_file_key(file);
 	int ret;
 
 	_enter("{%x:%u},%u", vnode->fid.vid, vnode->fid.vnode, fl->fl_type);
@@ -264,10 +327,6 @@ static int afs_do_setlk(struct file *file, struct file_lock *fl)
 	if (fl->fl_start != 0 || fl->fl_end != OFFSET_MAX)
 		return -EINVAL;
 
-	ret = afs_init_lock_manager();
-	if (ret < 0)
-		return ret;
-
 	fl->fl_ops = &afs_lock_ops;
 	INIT_LIST_HEAD(&fl->fl_u.afs.link);
 	fl->fl_u.afs.state = AFS_LOCK_PENDING;
@@ -278,7 +337,7 @@ static int afs_do_setlk(struct file *file, struct file_lock *fl)
 
 	/* make sure we've got a callback on this file and that our view of the
 	 * data version is up to date */
-	ret = afs_vnode_fetch_status(vnode, NULL, key);
+	ret = afs_validate(vnode, key);
 	if (ret < 0)
 		goto error;
 
@@ -315,7 +374,7 @@ static int afs_do_setlk(struct file *file, struct file_lock *fl)
 		set_bit(AFS_VNODE_LOCKING, &vnode->flags);
 		spin_unlock(&vnode->lock);
 
-		ret = afs_vnode_set_lock(vnode, key, type);
+		ret = afs_set_lock(vnode, key, type);
 		clear_bit(AFS_VNODE_LOCKING, &vnode->flags);
 		switch (ret) {
 		case 0:
@@ -418,7 +477,7 @@ given_lock:
 	/* again, make sure we've got a callback on this file and, again, make
 	 * sure that our view of the data version is up to date (we ignore
 	 * errors incurred here and deal with the consequences elsewhere) */
-	afs_vnode_fetch_status(vnode, NULL, key);
+	afs_validate(vnode, key);
 
 error:
 	spin_unlock(&inode->i_lock);
@@ -441,7 +500,7 @@ vfs_rejected_lock:
 static int afs_do_unlk(struct file *file, struct file_lock *fl)
 {
 	struct afs_vnode *vnode = AFS_FS_I(file->f_mapping->host);
-	struct key *key = file->private_data;
+	struct key *key = afs_file_key(file);
 	int ret;
 
 	_enter("{%x:%u},%u", vnode->fid.vid, vnode->fid.vnode, fl->fl_type);
@@ -476,7 +535,7 @@ static int afs_do_unlk(struct file *file, struct file_lock *fl)
 static int afs_do_getlk(struct file *file, struct file_lock *fl)
 {
 	struct afs_vnode *vnode = AFS_FS_I(file->f_mapping->host);
-	struct key *key = file->private_data;
+	struct key *key = afs_file_key(file);
 	int ret, lock_count;
 
 	_enter("");
@@ -490,7 +549,7 @@ static int afs_do_getlk(struct file *file, struct file_lock *fl)
 	posix_test_lock(file, fl);
 	if (fl->fl_type == F_UNLCK) {
 		/* no local locks; consult the server */
-		ret = afs_vnode_fetch_status(vnode, NULL, key);
+		ret = afs_fetch_status(vnode, key);
 		if (ret < 0)
 			goto error;
 		lock_count = vnode->status.lock_count;